Season the chicken generously with salt and pepper. Let stand for 30 minutes to 1 hour at room temperature.
Heat the oven to 400°F. Put an enameled cast-iron Dutch oven over medium heat. Add the butter and shallots and cook, stirring, until softened and lightly browned, about 5 minutes. Add the garlic and chopped tarragon and cook for 1 minute (be careful not to let the garlic brown). Arrange the chicken thighs in the pot in one layer, add the broth and wine, and bring to a simmer.
Put the lid on and place the pot on the middle shelf of the oven. Bake for 15 minutes, then lower the heat to 350°F and continue baking for 45 minutes, or until the thighs are tender. Put the thighs on a platter, cover loosely, and keep warm.
Strain the pan juices through a fine sieve into a saucepan and spoon off any rising fat. Place the pan over medium-high heat, add the crème fraîche and lemon zest, and simmer until the sauce is slightly thickened, about 5 minutes. Taste and adjust the seasoning.
Spoon the sauce over the chicken, garnish with tarragon leaves, and serve. A sprinkling of very thinly sliced scallions and chives could also be nice.
Tarragon Chicken with Vermicelli
hicken breasts bathed in a delicate mustard tarragon sauce.
6 large chicken thighs (about 3 pounds)
Salt and pepper
2 tablespoons unsalted butter
2 shallots, finely diced
2 garlic cloves, grated or minced
2 teaspoons chopped tarragon, plus whole leaves for garnish